linux/kernel/audit.c, branch v2.6.24

[PATCH] audit: watching subtrees

2007-10-21T06:37:45Z

New kind of audit rule predicates: "object is visible in given subtree". The part that can be sanely implemented, that is. Limitations: * if you have hardlink from outside of tree, you'd better watch it too (or just watch the object itself, obviously) * if you mount something under a watched tree, tell audit that new chunk should be added to watched subtrees * if you umount something in a watched tree and it's still mounted elsewhere, you will get matches on events happening there. New command tells audit to recalculate the trees, trimming such sources of false positives. Note that it's _not_ about path - if something mounted in several places (multiple mount, bindings, different namespaces, etc.), the match does _not_ depend on which one we are using for access. Signed-off-by: Al Viro

whitespace fixes: system auditing

2007-10-18T21:37:25Z

Just removing white space at the end of lines. Signed-off-by: Daniel Walker Cc: David Woodhouse Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[NET]: make netlink user -> kernel interface synchronious

2007-10-11T04:15:29Z

This patch make processing netlink user -> kernel messages synchronious. This change was inspired by the talk with Alexey Kuznetsov about current netlink messages processing. He says that he was badly wrong when introduced asynchronious user -> kernel communication. The call netlink_unicast is the only path to send message to the kernel netlink socket. But, unfortunately, it is also used to send data to the user. Before this change the user message has been attached to the socket queue and sk->sk_data_ready was called. The process has been blocked until all pending messages were processed. The bad thing is that this processing may occur in the arbitrary process context. This patch changes nlk->data_ready callback to get 1 skb and force packet processing right in the netlink_unicast. Kernel -> user path in netlink_unicast remains untouched. EINTR processing for in netlink_run_queue was changed. It forces rtnl_lock drop, but the process remains in the cycle until the message will be fully processed. So, there is no need to use this kludges now. Signed-off-by: Denis V. Lunev Acked-by: Alexey Kuznetsov Signed-off-by: David S. Miller

[NET]: Support multiple network namespaces with netlink

2007-10-10T23:49:09Z

Each netlink socket will live in exactly one network namespace, this includes the controlling kernel sockets. This patch updates all of the existing netlink protocols to only support the initial network namespace. Request by clients in other namespaces will get -ECONREFUSED. As they would if the kernel did not have the support for that netlink protocol compiled in. As each netlink protocol is updated to be multiple network namespace safe it can register multiple kernel sockets to acquire a presence in the rest of the network namespaces. The implementation in af_netlink is a simple filter implementation at hash table insertion and hash table look up time. Signed-off-by: Eric W. Biederman Signed-off-by: David S. Miller

Freezer: make kernel threads nonfreezable by default

2007-07-17T17:23:02Z

Currently, the freezer treats all tasks as freezable, except for the kernel threads that explicitly set the PF_NOFREEZE flag for themselves. This approach is problematic, since it requires every kernel thread to either set PF_NOFREEZE explicitly, or call try_to_freeze(), even if it doesn't care for the freezing of tasks at all. It seems better to only require the kernel threads that want to or need to be frozen to use some freezer-related code and to remove any freezer-related code from the other (nonfreezable) kernel threads, which is done in this patch. The patch causes all kernel threads to be nonfreezable by default (ie. to have PF_NOFREEZE set by default) and introduces the set_freezable() function that should be called by the freezable kernel threads in order to unset PF_NOFREEZE. It also makes all of the currently freezable kernel threads call set_freezable(), so it shouldn't cause any (intentional) change of behaviour to appear. Additionally, it updates documentation to describe the freezing of tasks more accurately. [akpm@linux-foundation.org: build fixes] Signed-off-by: Rafael J. Wysocki Acked-by: Nigel Cunningham Cc: Pavel Machek Cc: Oleg Nesterov Cc: Gautham R Shenoy Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Audit: add TTY input auditing

2007-07-16T16:05:47Z

Add TTY input auditing, used to audit system administrator's actions. This is required by various security standards such as DCID 6/3 and PCI to provide non-repudiation of administrator's actions and to allow a review of past actions if the administrator seems to overstep their duties or if the system becomes misconfigured for unknown reasons. These requirements do not make it necessary to audit TTY output as well. Compared to an user-space keylogger, this approach records TTY input using the audit subsystem, correlated with other audit events, and it is completely transparent to the user-space application (e.g. the console ioctls still work). TTY input auditing works on a higher level than auditing all system calls within the session, which would produce an overwhelming amount of mostly useless audit events. Add an "audit_tty" attribute, inherited across fork (). Data read from TTYs by process with the attribute is sent to the audit subsystem by the kernel. The audit netlink interface is extended to allow modifying the audit_tty attribute, and to allow sending explanatory audit events from user-space (for example, a shell might send an event containing the final command, after the interactive command-line editing and history expansion is performed, which might be difficult to decipher from the TTY input alone). Because the "audit_tty" attribute is inherited across fork (), it would be set e.g. for sshd restarted within an audited session. To prevent this, the audit_tty attribute is cleared when a process with no open TTY file descriptors (e.g. after daemon startup) opens a TTY. See https://www.redhat.com/archives/linux-audit/2007-June/msg00000.html for a more detailed rationale document for an older version of this patch. [akpm@linux-foundation.org: build fix] Signed-off-by: Miloslav Trmac Cc: Al Viro Cc: Alan Cox Cc: Paul Fulghum Cc: Casey Schaufler Cc: Steve Grubb Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

audit: add spaces on either side of case "..." operator.

2007-05-08T18:15:09Z

Following the programming advice laid down in the gcc manual, make sure the case "..." operator has spaces on either side. According to: http://gcc.gnu.org/onlinedocs/gcc-4.1.2/gcc/Case-Ranges.html#Case-Ranges: "Be careful: Write spaces around the ..., for otherwise it may be parsed wrong when you use it with integer values." Signed-off-by: Robert P. J. Day Cc: Al Viro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[NETLINK]: Switch cb_lock spinlock to mutex and allow to override it

2007-04-26T05:29:03Z

Switch cb_lock to mutex and allow netlink kernel users to override it with a subsystem specific mutex for consistent locking in dump callbacks. All netlink_dump_start users have been audited not to rely on any side-effects of the previously used spinlock. Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller

[NETLINK]: Introduce nlmsg_hdr() helper

2007-04-26T05:26:34Z

For the common "(struct nlmsghdr *)skb->data" sequence, so that we reduce the number of direct accesses to skb->data and for consistency with all the other cast skb member helpers. Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller

[SK_BUFF]: Convert skb->tail to sk_buff_data_t

2007-04-26T05:26:28Z

So that it is also an offset from skb->head, reduces its size from 8 to 4 bytes on 64bit architectures, allowing us to combine the 4 bytes hole left by the layer headers conversion, reducing struct sk_buff size to 256 bytes, i.e. 4 64byte cachelines, and since the sk_buff slab cache is SLAB_HWCACHE_ALIGN... :-) Many calculations that previously required that skb->{transport,network, mac}_header be first converted to a pointer now can be done directly, being meaningful as offsets or pointers. Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller